Abstract: A method for producing metallic magnesium by vacuum circulating silicothermic process and apparatus thereof The method comprises the following steps: passing molten ferrosilicon (109) of 1350˜1600° C. and magnesium ore powder containing magnesia blended therein through a vacuum container (104) with a vacuum of 350˜10000 Pa periodically in a manner of circulating flow, and collecting liquid magnesium (201), i.e. the magnesium vapor released upon condensing. The apparatus comprises a heating container (101) and a vacuum container (104) connected with an elevating dip pipe (102) and a falling dip pipe (103) whose lower ends immersed into the molten ferrosilicon (109) in the heating container (101). An inert gas blowing device is inserted into the elevating dip pipe (102) wall. The method and apparatus thereof can improve productivity.

Abstract: A process of producing magnesium metal includes providing magnesium carbonate, and reacting the magnesium carbonate to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The carbon dioxide is used as a reactant in a second process. In another embodiment of the process, a magnesium silicate is reacted with a caustic material to produce magnesium hydroxide. The magnesium hydroxide is reacted with a source of carbon dioxide to produce magnesium carbonate. The magnesium carbonate is reacted to produce a magnesium-containing compound and carbon dioxide. The magnesium-containing compound is reacted to produce magnesium metal. The invention also relates to the magnesium metal produced by the processes described herein.

Abstract: The present invention provides a method for producing a metal vapor that includes the steps of combining a metal and graphite in a vessel to form a mixture; heating the mixture to a first temperature in an argon gas atmosphere to form a metal carbide; maintaining the first temperature for a period of time; heating the metal carbide to a second temperature to form a metal vapor; withdrawing the metal vapor and the argon gas from the vessel; and separating the metal vapor from the argon gas. Metal vapors made using this method can be used to produce uniform powders of the metal oxide that have narrow size distribution and high purity.

Abstract: A method of producing magnesium vapor at substantially atmospheric pressure. The method comprises feeding into the reaction zone of a reduction furnace magnesium-oxide containing materials and metal reductants and then heating the magnesium-oxide containing materials and the metal reductants in the reaction zone to an operating temperature to create a slag composition. The slag composition has a phase diagram including a two-phase liquid and solid region. The feeding of the magnesium-oxide containing material and the metal reductant into the furnace bath are controlled such that the slag composition at the operating temperature is within the two-phase liquid and solid region of the phase diagram. In this way, reactions occur to produce magnesium vapor at substantially atmospheric pressure. A method of producing magnesium metal is also disclosed.

Abstract: Magnesium is produced by the metallothermic reduction of MgO in a molten slag bath comprised of MgO, Al.sub.2 O.sub.3 and CaO together with oxide formed from the reducing metal. The composition of the slag is controlled during at least a first stage of the reduction so that it is wholly within the periclased region of its phase diagram and at least in the surface region, has a substantially constant liquidus temperature. The surface region of the slag is maintained by direct heating (e.g. by a plasma) at or close to the liquidus temperature.

Abstract: In a metallothermic process for reducing rare earth metal salts to produce pure rare earth metals and metal alloys, e.g. neodymium or neodymium/iron alloy for use in manufacturing neodymium/boron/iron permanent magnets, including adding pure metallic iron, such as iron flake, to a mixture of metal salt, such as neodymium chloride, and a reducing metal source, such as calcium/magnesium alloy, heating in a crucible in a preheated high temperature furnace with stirring to a temperature of 900 degrees C. under a flow of argon, separating the metal from the salt formed, and purifying the metal via distillation.